Demon Princess Illyria
by syrensereana
Summary: When the sister of Rin and Yukio comes for a visit, what chaos will happen? and what truth will the twins learn? Warning rating may change. DISCLAIMER:I do not own Blue exorcist. NOTE: ORIGINAL FAN FICTION BELONGS TO RYOYA I will have my disclaimers here so don t expect them in every chapter. Arigato for reading!
1. Chapter 1

**Hi! I`m Syrensereana! I`m taking over Demon Princess Illyria from RYOYA. **

**Disclaimer: i do not own Ao No Exorcist (blue exorcist) or the original idea or this fan fiction and the oc in this fan fiction.** **Ao No Exorcist belongs to the original creator of Ao No Exorcist. the original idea for this fan fiction and the oc in it belong to RYOYA. so do the first 19 chapters ,if you don't count the chapter after that that is asking for someone else to take over, and a good part 20th chapter. ** **Chapter one**

As I walked through Gehenna to my father`s home I felt quite irritated. My father, Satan, had gone over the line possessing my younger brother Yukio. After that he had refused to speak to anyone, even me. His cutest daughter! I could feel the vein in my forehead begin to pulse in time with my heels on the flooring.

_I swear I am going to kill him this this time._ I thought as i kicked open the doors to his chambers. Sure my father could stoop pretty low sometimes, but this?! Absolutely unforgivable! I was about to start yelling at him when I saw him staring at a picture of Rin and Yukio`s mother i was able to get for him. I saw through the reflection that he was crying. My anger shrank instantly as I saw him like that.

"Father, I wish a word with you." I said in a very respectful tone. Even though he loves me he can be very cruel when he was in a bad mood. He gave the picture one last look before walking up to hug me. If God could see this now. Satan, ruler of Gehenna, acting so tenderly.

"Yes darling, what do you want? A new dress perhaps?" He laughed.

"I wish to go to the world of Assiah, to see Rin and Yukio. Don`t you think they should know about me?" I asked, Father for the longest time forbade me from ever stepping foot on Assiah again. why? Because I had caused the Blue Night sixteen years ago. Well not me per say, I was just a child then. Those monks thought to try to exorcise me knowing full well it would cause me pain. Since I am more demon than I am human. I was scared; mother was killed because father had possessed her to save me. Even though the Blue Flames didn't burn her, trying to channel them though father had proved to be too much. So father went on a rage and burned almost everyone there, when I was safe he took me here.

"You know how i feel about that. But I think your old enough and in control enough to. You have my permission." He smiled a sad smile, and I knew he wasn't overly thrilled. But I couldn't contain my excitement. Sure I had a traumatic experience but I was willing to try. I jumped up and down in elation, Hugging father in between bounces.

"Thank you daddy! I love you and I promise I won`t hurt anyone! I gotta go pack!" I squealed While skipping to the door.

"I love you to Illyria, my angel." he called to me as I raced out an ran down the hall towards my room.

**I hope you all liked it, i made some minor alterations to the original but it was all just adding variety to words so it isn`t just said the whole time for example (not that it was, i just dont like using the word said much unless i cant think of anything else to use). please comment and review! all constructive criticism should please be said through pm! Thank you!**


	2. Chapter 2

Packed and ready to go I stood by my father at the gate to take me to Assiah, he still looked sad. I smiled and waved, and he returned my gesture.

"Remember, Mephisto will be waiting for you on the other side to take you to your brothers. If they are mean to you tell me and i will send Amaimon after them!" he yelled.

"Will do! Love you!" I yelled back as I walked through the gate, it was pure darkness as I traveled through. Then as soon as I began it ended and I was bathed in a light I never remember seeing.

_I think it`s called...sunlight. _I thought idly looking around for Mephisto. I saw him over by a fountain; one of many at true cross academy. i sauntered over to him to make it look like i knew what I was seeing and not stopping at everything i have never seen before.

"Good afternoon, princess. Your father asked me to take you to Rin and Yukio. He also said that if you wish i can enroll you here if you wish to stay." He said with a smile.

"Really!? I can stay!? YAY!" I screamed. What are you planning with that smile?

"Good thing I had all the paperwork done, huh? Now shall we go meet your brothers? They are in class now so we won`t have to find them later." he said gesturing me to a door. He took out a key and pushed it into the lock on the door. When he opened the door we stepped into a hallway that seemed to have no ceiling. I stumbled after him while still trying to see the ceiling with no avail. We stopped in front of another door.

"Here we go, Yukio is teaching now so you can meet them both if you like."

I shook my head and we went in, with me hiding behind Mephisto. I could tell there were humans inside, and I am very afraid of them for obvious reasons.

"Yukio, I`m very sorry for interrupting your class but I have a new student whom I think you and Rin will like very much." Mephisto cut Yukio off where he was in the lesson he was trying, with no avail, to get Rin to learn something from.

"Not a problem chairman. Where is this new student?" Yukio asked.

I peeked around my brother`s arm to come face to face with a male copy of Yuri. He is very handsome.

"H-hello, my name is Illyria. I-it`s nice t-to meet you." I stuttered. Yukio smiled warmly."No need to be scared, come on out." Yukio coughed to clear his throat, here we go.

"Actually, Yukio-kun, Illyria here is very afraid of humans. Also, she is your sister I am expecting you and Rin to look out for her." Mephisto said as he walked out of the room. I was trembling, I knew I could kill them if I had to but I am still scared. Everyone stared at me, some with shock, others with anger. I could feel daggers from the one in the black with the blond stripe in the center of his head. He got up abruptly causing me to shriek a little.

"What the hell?! Another one of Satan's spawn?! Rin and Yukio are okay, but how are we sire this one ain`t gonna kill us?!" he asked angrily. Yukio gave the kid one of the looks teachers and parents give kids who are misbehaving, causing the kid to sit back down in his seat grumbling. I looked t Yukio, still shaking.

"I-if it`s too m-much trouble i-i can leave." I stuttered more from the pain that was beginning to start. Stupid illness; one of which there was no cure unless you count death as a cure.

"NO, you're fine. They're just a tiny bit afraid of you, that's all. Why don't you tell us about yourself? Everyone here is Rin`s friend, and i`m sure they'll be your friends too." Yukio replied to me in a calming tone of voice.

"O-okay. m-my name is Illyria Lucefinia; i am sixteen years old and i have lived in Gehenna for the past eleven years." I said gaining control over my heart. One of the guys next to the one who was yelling at me stood up and walked over to me and held his hand out.

"My names Shima, nice to meet you Illyria. The guy who likes to yell is Bon, and Konekomaru is the bald one next to him." I wasn't sure what to do, do I shake his hand? I timidly shook it in return. he grabbed my wrist and dragged me to the other students.

"The blonde girl is Shiemi, that's Rin beside her. And the purplish-black haired girl is Kamiki.


	3. Chapter 3

**sorry I forgot disclaimer on last chapter, ao no exorcist** **doesn`t belong to me, nor do the first twenty chapters, I took over this fanfiction from ryoya**

**Arigato for reading!**

* * *

I realized that I was still holding Shima's hand, I jerked away with a slight gasp. Yukio glanced at his watch then addressed the class.  
"Alright, we have a few minutes left of class. So then why don't we take this time to learn about our new classmate with a little Q and A?" Yukio asked. Then one named Bon was the first one up, his angry expression unchanged.  
"Rin is our friend so we trust him. I don't know you so why don't you tell us where you were all this time?"  
"W-well, I was living in Gehenna at the time and have been for several years. A-and no one c-can leave or enter without consulting father." I said weakly. Why do I have to share a class with humans?  
Because we are in an exorcist school? Yeah, that would be it.  
"Miss Illyria, are you perhaps….afraid of humans?" asked Konekomaru. I nodded remembering the pain I had received at the hands of humans.  
"Aw that's silly. If you want to fear someone, fear Yukio's pop quizzes." Shima laughed. It made me feel better, strange that I felt at ease near him. Like there wasn't a care in the world.  
"So can you control the Blue Flames?" Rin asked.  
"W-well yes but I am better at controlling the Green flames better. Blue burns, green lets you make illusions, red is for barriers, purple is for curses, yellow is for healing, and orange is summoning." I finished my explanation, feeling just a little smug. Rin just stared in wonder, he reminded me of a child. Strange how he was the spitting image of father.  
"If you have been in Gehenna a long time, have you seen your mom yet?" Rin asked. I felt that all too familiar pain.  
"N-no, my mother died a long time ago. But I have this." I said pulling out the locket Daddy gave me a few years ago. I popped it open and green flames came out spiraling to the table, settling in a sparkling image of my mother. Rin's eyes held a sadness to them, I guess he was sorry he asked me about her.  
"Shortly before I went to live in Gehenna, my mother was attacked on her way home from the store. She lived but later died in a car crash while I was at school."  
I heard muttered apologies and even Bon's face softened. Maybe humans weren't as bad as I thought. I closed the locket and let it fall back underneath my shirt. Yes I missed my mother but then, I didn't really have memories of her other than what my father had showed me. So Rin and Yukio's mother Yuri became a surrogate for me.  
Shima stepped up." Since you're new to Assiah how about we show you around?"  
"I would like that, in fact I have a strange question. Umn, what were those white things above? Outside I mean." They all looked at me strangely.  
"You mean the clouds?" the asked at once.  
So that's what they were? Clouds?  
I absently heard the bell ring and everyone was moving to leave for the day. As we walked everyone chatted idly, even Yukio added his opinion every now and then. When Rin turned the knob on the door to the outside, I was momentarily blinded by the light in the….What was it called again? Oh! The sky.  
"Hey I didn't notice before, but your eyes are pretty cool. One green and the other blue." Rin said smiling.  
"U-umn Yukio, Rin? I-if its o-okay can I c-call you b-b-brother?" I asked timidly, maybe they will laugh at me or get mad.  
"Sure!" they said together. I was so happy; I was finally going to get the family and friends I always wanted! Everyone was sitting down to lunch when I noticed I hadn't got one.  
"You wanna share Illyria?" asked Shima, holding his lunch out to me.  
"Oh no, I don't want to trouble you. I'll just go grab something from one of the stores here. I shall be right back!" I said as I bounced off.  
"So we have a new sister." Rin said through a mouthful.  
"Did you think we were the only ones?" Yukio asked.  
"No. but it's weird. She didn't know what the sky or clouds were. Do you really suspect something bad from such an innocent looking girl?" Shima and the rest nodded in agreement.  
"I don't know, guess we will just have to watch her and be careful."  
The finished eating in silence and still the mystery new sister had yet to return. They were all starting to get worried. They were braking into groups to go off to find her when a scream pierced their thoughts. Shima was the first to run to the sound.


	4. Chapter 4

Shima and the others rounded a corner that the scream came from, there were other students crowded around. So many that they Ex-wires had to push some out of the way until the burst forth from the mob. There, lying in the grass was Illyria completely unconscious. Yukio went to check her while Rin and Shima asked around to see if anyone saw what happened. Everyone said they got here after they heard her scream.

"Yukio-kun!" whispered a voice. Yukio looked down to see a small dog.

"Chairman, what happened?" Yukio hissed.

"She didn't tell you? Oh well not my place then. Take her to the dorms and I will be there shortly." Mephisto said as he trotted off. Yukio picked up the small girl and carried her bridal style. Someone this light and frail is a child of Satan? Yukio thought to himself, he laughed at the thought until he felt a chill go down his spine. It looked like Rin and the others felt the same thing, but what was it? A demon? Yukio motioned for the others to follow the short trip didn't seem to take any time at all. And just as he said, Mephisto was waiting with a very large syringe.

"Glad you could make it." he said.

"And what will that do?" Rin snapped. Guess you're still edgy huh? I sent to him.

"Simple her human body is weak; this will keep her strength up as long as she takes it." Mephisto grinned. Then just sauntered over to her and injected it before Rin or any of the others could stop him. The second it entered her blood stream, she spiked a fever. Even with her fever she looked more angel than a demon.

"Secondly that chill you felt was Satan trying to talk to you. You have to give him permission to or you just will keep getting that feeling." He stated as he vanished behind the dorms. Everyone was now nervous. Satan trying to talk to us? Why? Rin sent. I shook my head. Then we heard it and everyone force at the voice that could freeze fire and melt glaciers.

"So how was my daughters first day of school?" asked the stranger leaning against the door frame of the entrance to Yukio and Rin's dorm. The guy was truly terrifying, at about seven feet tall with black hair down to his shoulders. He wore black leather pants with a black sleeveless shirt and biker boots. With leather fingerless glove and an eye patch across his right eye. Everything about him screamed evil, Yukio looked to the others seeing them tremble.

"Who are you?!" I asked trying to keep my own voice from shaking. He just looked at me with an arrogant and amused look.

"Aw, I'm hurt. You don't recognize the face of your own dad?" He asked. He walked right up to me and shoved his arm right through me. "Don't look so worried my soul is the only thing here."

_Listen well everyone, I am placing the only thing I care about in your protection. If you fail or hurt her in any way, I will personally drag you to Hell and make the Saw movies look like a fun trip to Disney. His words echoed in our heads as he evaporated into mist, the guy was truly scary_. And all he wanted was to make sure his daughter was safe? This day is getting stranger and stranger. I looked at everyone and they seemed fine, no longer were they scared.

"Alright let's get inside." I said.


	5. Chapter 5

Illyria was dreaming, or she hoped she was anyway. She was lying on a table, looking through a child's eyes and thinking childish things. She looked around at the people gathered around and in front of her. They were chanting something she couldn't understand, something she was afraid of. He mother lay on the floor; she wasn't moving save for the steady rise and fall of her chest.

_Mommy! Daddy help! I am scared!_ Her child-like mind thought franticly. Her mother was strong and brave; she wasn't the kind of person to leave her daughter strapped to a table frightened. Something was very, very wrong. A man to her left dipped his hand in a gold bowl and splashed her with it, where ever the liquid touched burned her like fire. She screamed out in agony, why is this happening? What is happening?

"Please stop! You're hurting me!" She begged but no one seemed to care. Except for one man who whispered at her. Her hearing was always better; the man was all the way across the room.

"It's alright, we are trying to help you. Poor child, she doesn't even know she's possessed." He murmured. The man splashed her again, the welts from the liquid formed quickly. Even through her clothes the pain was unbearable. Her mother began to move, within minutes her mother was throwing people around like the weighed no more than dolls.

"Its okay baby, Mama is going to get you out of here. Okay? I need you to not be scared." Her mother shouted. She tried as hard as she could, but she was still so scared. Why were these people hurting her? She heard her mother scream and looked over to see what was the matter. Her mother was writhing on the floor, flames licking their way up her arm to engulf her whole body. She had apparently been knocked into a lamp. There strapped to a table, surrounded by strangers who hurt her, she watched as her mother died.

_No!_ Her mind roared. _My mom died in a car crash! This isn't real!_

Still locked away in her younger self's body, Illyria felt her own horror, pain, and hatred. Something inside her snapped. Gone was any soul reflected in her own eyes, it was replaced by something that had no problem killing any- and everyone. The shackles erupted in blue flames until they were nothing but ashes. She hissed in pain as some poured more water on her, then looked to him and he too burst into blue flames. She looked around at the people and one by one all were engulfed in a raging blue pyre. She walked to the door, passed the one who was whispering at her right to the door.

Once a normal looking door, it twisted into a gateway with large eyes. _Go through it angel. Daddy is on the other side waiting for you._ Her father's voice said clear as day. Illyria as a child around the age of five walked through it. This is all wrong! That was her last thought before she woke up to the sound of screaming.

Illyria stayed very still until she understood what was around her, she felt warm and that she was lying on something soft. A bed, maybe? People were shouting next to her, she could tell that everyone was here. She opened her eyes to see Rin standing next to her. What is going on? And why are they yelling so loud. She whined.

"What the hell do you mean she doesn't remember ever being here?!" Rin asked angrily.

"That's what Kuro said. After she went to Gehenna Satan locked away her memories to help her cope with the tragedy." Yukio said softly, there was a note of anger in his voice as well.

"So you want us to believe that the Blue Night was cause by her?" Bon shouted. I head a smack. "OW! Why did you hit me you bastard?"

"Don't shout so loud! You might wake her!" Rin hissed.

"But she said she was sixteen. She would have been a baby at the time." Konekomaru said.

"True, that what she remembers. But she doesn't age like we do, she chose to go into stasis for a while so her body could get used to the differences in Gehenna. Apparently while in stasis the body and mind don't age." Yukio said, he is smart.

_No more…._ She thought. _It's not true…_

Illyria felt a sharp pain go through her; suddenly she couldn't hear them anymore. They were still talking but there was no sound at all. Then for no reason she fell into a deep sleep again.


End file.
